Status saving is a technique to write data required for resuming an operation, onto a nonvolatile storage medium. This is performed in case of an unexpected event of a sudden cutoff of power supply to an apparatus. As with conventional measures against power outages, this processing is considered essential for stable operations of the apparatus. On the other hand, status restoring is a technique to resume the operation which was being executed before the power cutoff, after the power supply to the apparatus is restarted, based on the data written onto the nonvolatile storage medium. In playback apparatuses which execute AV playback of DVD-Video, the status saving and the status restoring are performed as follows: before AV playback stops, a physical or a logical playback position is written onto the nonvolatile storage medium; and the next playback is resumed from the playback position written onto the nonvolatile storage medium.    Patent Document 1: Japanese Patent No. 3438729    Patent Document 2: Japanese Laid-Open Patent Application No. 2003-77222    Patent Document 3: Japanese Laid-Open Patent Application No. S62-169218